Power Supply

Control programmable power supplies to set voltage, current, and protection thresholds for your DUT.

Import

from lager import Net, NetType

Methods

Method	Description
`set_voltage()`	Set output voltage
`set_current()`	Set output current limit
`voltage()`	Read measured voltage
`current()`	Read measured current
`power()`	Read measured power
`enable()`	Enable power output
`disable()`	Disable power output
`set_ovp()`	Set over-voltage protection threshold
`set_ocp()`	Set over-current protection threshold
`get_ovp_limit()`	Get over-voltage protection limit
`get_ocp_limit()`	Get over-current protection limit
`is_ovp()`	Check if OVP fault is active
`is_ocp()`	Check if OCP fault is active
`clear_ovp()`	Clear over-voltage protection fault
`clear_ocp()`	Clear over-current protection fault
`state()`	Print the power state to the box’s hardware-service log; returns `None`
`get_full_state()`	Print the extended state to the same log; returns `None`
`set_mode()`	Keithley 2281S only: put the instrument into DC power-supply mode
`disable_ocp(channel)`	Turn over-current protection off, on instruments that can
`disable_ovp(channel)`	Turn over-voltage protection off, on instruments that can
`get_monitor_state(channel)`	Read the full state of one channel in a single call; returns a dict
`get_monitor_states(channels)`	`get_monitor_state()` for several channels; returns a dict keyed by channel

Method Reference

`Net.get(name, type=NetType.PowerSupply)`

Get a power supply net by name.

from lager import Net, NetType

psu = Net.get('VDD', type=NetType.PowerSupply)

Parameters:

Parameter	Type	Description
`name`	`str`	Name of the power supply net
`type`	`NetType`	Must be `NetType.PowerSupply`

Returns: Power supply Net instance

`set_voltage(value)`

Set the output voltage.

psu.set_voltage(3.3)  # Set to 3.3V

Parameter	Type	Description
`value`	`float`	Target voltage in volts

`set_current(value)`

Set the output current limit.

psu.set_current(0.5)  # Set limit to 0.5A

Parameter	Type	Description
`value`	`float`	Current limit in amps

`voltage()`

Read the measured output voltage.

v = psu.voltage()
print(f"Voltage: {v}V")

Returns: float - Measured voltage in volts

`current()`

Read the measured output current.

i = psu.current()
print(f"Current: {i}A")

Returns: float - Measured current in amps

`power()`

Read the measured output power.

p = psu.power()
print(f"Power: {p}W")

Returns: float - Measured power in watts

`enable()`

Enable the power output.

psu.enable()

`disable()`

Disable the power output.

psu.disable()

`set_ovp(limit)`

Set over-voltage protection threshold. When the measured voltage exceeds this threshold, the output is automatically disabled. On a Keithley 2281S, an OVP below the voltage setpoint raises an error. The other drivers accept it.

psu.set_ovp(3.6)  # Trip at 3.6V

Parameter	Type	Description
`limit`	`float`	OVP threshold in volts

`set_ocp(limit)`

Set over-current protection threshold. When the measured current exceeds this threshold, the output is automatically disabled.

psu.set_ocp(1.0)  # Trip at 1.0A

Parameter	Type	Description
`limit`	`float`	OCP threshold in amps

`get_ovp_limit()`

Get the configured OVP limit.

ovp = psu.get_ovp_limit()
print(f"OVP limit: {ovp}V")

Returns: float - OVP threshold in volts

`get_ocp_limit()`

Get the configured OCP limit.

ocp = psu.get_ocp_limit()
print(f"OCP limit: {ocp}A")

Returns: float - OCP threshold in amps

`is_ovp()`

Check if an over-voltage fault is active.

if psu.is_ovp():
    print("OVP fault detected!")

Returns: bool - True if OVP fault is active

`is_ocp()`

Check if an over-current fault is active.

if psu.is_ocp():
    print("OCP fault detected!")

Returns: bool - True if OCP fault is active

`clear_ovp()`

Clear over-voltage protection fault.

psu.clear_ovp()

`clear_ocp()`

Clear over-current protection fault.

psu.clear_ocp()

`state()`

Print comprehensive power supply state including channel, enabled status, mode (CV/CC), measured voltage/current/power, and protection status. The call runs in the box’s hardware service. The text goes to /tmp/lager-hardware-service.log on the box, not to your script, and the call returns None. To read the state in a script, use get_monitor_state(). See #845.

psu.state()

Example output:

Channel: CH1
Enabled: ON
Mode: CV
Voltage: 3.3000
Current: 0.1520
Power: 0.5016
OCP Limit: 1.0000
    OCP Tripped: NO
OVP Limit: 3.6000
    OVP Tripped: NO

`get_full_state()`

Print extended state including all measurements, configured setpoints, protection limits, and hardware maximum ratings. Like state(), it prints to the hardware-service log and returns None.

psu.get_full_state()

Example output:

Channel: CH1
Enabled: ON
Mode: CV
Voltage: 3.3000
Current: 0.1520
Power: 0.5016
Voltage_Set: 3.3000
Current_Set: 1.0000
OCP Limit: 1.0000
    OCP Tripped: NO
OVP Limit: 3.6000
    OVP Tripped: NO
Voltage_Max: 30.0000
Current_Max: 3.0000

Additional fields beyond state():

Voltage_Set / Current_Set - Configured setpoints
Voltage_Max / Current_Max - Hardware channel ratings

`get_monitor_state(channel)`

Read the full state of one channel in a single call, and return it as a dict. This is the way to read the state in a script.

state = psu.get_monitor_state(psu.channel)
print(state['voltage'], state['current'], state['enabled'])

Key	Description
`voltage`, `current`, `power`	Measured values, or `None` when a read fails
`enabled`	`True`, `False`, or `None` when unknown
`mode`	`CV` or `CC`
`voltage_set`, `current_set`	Configured setpoints
`voltage_max`, `current_max`	Hardware channel ratings
`ocp_limit`, `ocp_tripped`, `ovp_limit`, `ovp_tripped`	Protection limits and trip state

Pass the net’s channel. With no channel, a multi-channel supply such as a DP832 reads the output that is selected on its front panel (#846). get_monitor_states([1, 2]) reads several channels and returns {'1': {...}, '2': {...}}.

`disable_ocp(channel)` / `disable_ovp(channel)`

Turn over-current or over-voltage protection off. Setting a limit with set_ocp() or set_ovp() turns it back on.

psu.disable_ovp(psu.channel)

Instrument	Result
Rigol DP700, Rigol DP800, Keysight E36200	Protection turns off
Keysight E36300, Keithley 2281S, Siglent SPD1000X, EA	Raises an error

Pass the net’s channel. With no channel, a multi-channel supply acts on the output that is selected on its front panel (#846). A net with a max_voltage safety limit refuses to turn OVP off, and a net with max_current refuses to turn OCP off.

Examples

Basic Power Control

from lager import Net, NetType

# Get power supply net
psu = Net.get('VDD', type=NetType.PowerSupply)

# Configure output
psu.set_voltage(3.3)
psu.set_current(0.5)

# Enable output
psu.enable()

# Read measurements
print(f"Voltage: {psu.voltage():.2f}V")
print(f"Current: {psu.current():.3f}A")
print(f"Power: {psu.power():.3f}W")

# Disable when done
psu.disable()

With Protection Thresholds

from lager import Net, NetType
import time

psu = Net.get('VDD', type=NetType.PowerSupply)

# Configure voltage/current
psu.set_voltage(5.0)
psu.set_current(0.5)

# Set protection thresholds
psu.set_ovp(5.5)  # Trip at 5.5V
psu.set_ocp(0.6)  # Trip at 0.6A

# Enable output
psu.enable()
print("Power enabled")

# Monitor for faults
time.sleep(1)
if psu.is_ocp():
    print("OCP fault! Clearing...")
    psu.clear_ocp()

if psu.is_ovp():
    print("OVP fault! Clearing...")
    psu.clear_ovp()

# Clean up
psu.disable()

Monitor Power Consumption

from lager import Net, NetType
import time

psu = Net.get('VDD', type=NetType.PowerSupply)
psu.set_voltage(3.3)
psu.set_current(1.0)
psu.enable()

# Log power consumption
for sample in range(10):
    v = psu.voltage()
    i = psu.current()
    p = psu.power()
    print(f"V={v:.2f}V, I={i:.3f}A, P={p:.3f}W")
    time.sleep(1)

psu.disable()

Full State Inspection

from lager import Net, NetType

psu = Net.get('VDD', type=NetType.PowerSupply)
psu.set_voltage(3.3)
psu.set_ovp(3.6)
psu.set_ocp(0.5)
psu.enable()

# Read the full state as a dict
print(psu.get_monitor_state(psu.channel))

psu.disable()

Supported Hardware

Manufacturer	Model Series	Channels	Features
Rigol	DP832 / DP832A	3	Ch1-2: 30V/3A, Ch3: 5V/3A
Rigol	DP821	2	Ch1: 60V/1A, Ch2: 8V/10A
Rigol	DP811 / DP811A	1	20V/10A or 40V/5A
Rigol	DP711 / DP712	1	DP711: 30V/5A, DP712: 50V/3A
Siglent	SPD1168X / SPD1305X	1	SPD1168X: 16V/8A, SPD1305X: 30V/5A. No OVP or OCP
Keithley	2281S	1	20V/6A/120W, battery simulator mode
Keysight	E36200 series	2	E36233A: 30V/20A per channel
Keysight	E36300 series	3	E36311A/12A/13A
EA	PSB 10060-60 / 10080-60	1	Two-quadrant. See the warning below

An EA supply does not work through Net.get() today. set_voltage(), set_current(), set_ovp(), set_ocp(), enable() and disable() fail with “Function not found”. Use lager supply for an EA supply. See #843.

Notes

Net must be configured as NetType.PowerSupply
Call enable() to turn on the output after setting voltage/current
Always call disable() when finished
Protection faults automatically disable output; use clear_ovp() or clear_ocp() after addressing the fault
On a Keithley 2281S, an OVP below the voltage setpoint raises an error
Voltage and current limits depend on hardware capabilities
Multi-channel supplies: each channel is configured as a separate net
state() and get_full_state() print to the box’s hardware-service log and return None; use voltage(), current(), power() or get_monitor_state() to get values in code

Getting Started

Development

Power & Simulation

Measurement

I/O & Communication

Utilities

Power Supply

Import

Methods

Method Reference

`Net.get(name, type=NetType.PowerSupply)`

`set_voltage(value)`

`set_current(value)`

`voltage()`

`current()`

`power()`

`enable()`

`disable()`

`set_ovp(limit)`

`set_ocp(limit)`

`get_ovp_limit()`

`get_ocp_limit()`

`is_ovp()`

`is_ocp()`

`clear_ovp()`

`clear_ocp()`

`state()`

`get_full_state()`

`get_monitor_state(channel)`

`disable_ocp(channel)` / `disable_ovp(channel)`

Examples

Basic Power Control

With Protection Thresholds

Monitor Power Consumption

Full State Inspection

Supported Hardware

Notes

​Import

​Methods

​Method Reference

​Net.get(name, type=NetType.PowerSupply)

​set_voltage(value)

​set_current(value)

​voltage()

​current()

​power()

​enable()

​disable()

​set_ovp(limit)

​set_ocp(limit)

​get_ovp_limit()

​get_ocp_limit()

​is_ovp()

​is_ocp()

​clear_ovp()

​clear_ocp()

​state()

​get_full_state()

​get_monitor_state(channel)

​disable_ocp(channel) / disable_ovp(channel)

​Examples

​Basic Power Control

​With Protection Thresholds

​Monitor Power Consumption

​Full State Inspection

​Supported Hardware

​Notes

Import

Methods

Method Reference

`Net.get(name, type=NetType.PowerSupply)`

`set_voltage(value)`

`set_current(value)`

`voltage()`

`current()`

`power()`

`enable()`

`disable()`

`set_ovp(limit)`

`set_ocp(limit)`

`get_ovp_limit()`

`get_ocp_limit()`

`is_ovp()`

`is_ocp()`

`clear_ovp()`

`clear_ocp()`

`state()`

`get_full_state()`

`get_monitor_state(channel)`

`disable_ocp(channel)` / `disable_ovp(channel)`

Examples

Basic Power Control

With Protection Thresholds

Monitor Power Consumption

Full State Inspection

Supported Hardware

Notes